Rural Energy Partnership
SAUNDERS ISLAND PROJECT
The aim of this project is to significantly reduce the amount of fossil fuel required to provide adequate electricity to the farm and the 5 domestic dwellings at the main settlement by introducing a another sustainable technology.
The current energy system on Saunders Island is a wind hybrid system. It was installed in 2001 to supply the farm with 24 hour electricity. The demand for electricity has grown on the farm over the last decade and with diversification into tourism the energy system is undersized.
2 x 2.5kW Proven wind turbines, installed in 2001
1 x 15kW diesel generator, installed in 2001
2 x 4kW Trace Inverters, installed in 2001
660Ah battery bank, installed in 2001
The current system uses on average 3,000 litres of diesel a year costing £1,500 (Diesel price £0.50 per litre). It is estimated that the generator runs between 800 - 1,000 hours per year.
4 kW of Solar Photovoltaic Panels installed facing north at an angle of 20° is estimated to provide around 3200kWh per year of electricity. It is predicted this will reduce the running time of the generator by 250 hours a year, saving around £500 per annum.
After the award of the Rural Energy Partnership Development grant the design of the array began. The first thing that was to be decided was to install a roof mounted system or ground mounted system. Both have their advantages and disadvantages, the main ones being that a ground mounted system will generate more electricity but the mounting system costs will be higher, whereas the business could spend the same amount on upgrading an existing building and install the array on the roof out of the way of vehicles and animals but will generate less. The difference between the output was around 400kWh per year (around £50 extra fuel saving a year) but the difference in the investment was around £2,000 more for a ground mounted system.
The decision was made to install the array on the roof of an existing building at the settlement. We contacted the Falkland Islands Government Building Advisor to find out it any permits were required for the installation. The building advisor was very helpful and informed us that the array would not require planning permission but would require a building permit. The form was very easy and quick to complete and was submitted along with a drawing of the building and map of the settlement. Very quickly we received the approved building permit.
With all permissions in place the array was ordered in April 2015 through the local renewable supplier and installer PowerSense.
While the system was being shipped from the UK, it was thought it would be a good idea to get the electrical systems of the buildings connected to the generation system checked for safety. This work was carried out by FIC, with a proportion of the expense for the work on the domestic properties covered under the Domestic Electricity Safety Check and Improvement Grant Scheme. This scheme is managed by FIDC and is open to all domestic properties owners across the Falkland Islands to improve the electrical safety.
The installation started on the 15th August 2016 after the building had been re-cladded. The installation took around 5 Days (with help from the farm employees) as the array was commissioned on Wednesday 24th September 2016. The total cost of the installation was £4,230, if the system generates as predicted the payback will be 8.5years .
1. The array output from the installation on the 24th September 2016 until 31st January 2017.
The solar array has covered 75% of the demand of the business. The array was never expected to cover the high power demand of shearing. Over the above period the business has required the diesel generator to be operating for an estimated 66 hours. The business before the array was installed would normally operate the diesel generator for around 2 hours a day to cover the demand not met by the wind turbines. The diesel generator required 5 litres of fuel per hour to operate but as the installation of the solar array has reduced the operating time of the diesel generator by 192hour, 960 litres of diesel have not been burnt; a saving of £480 (diesel price at £0.50 per litre) over a three month period.
2. Period - 1st February 2017 until 31st May 2017
The array has been installed for over six months and is working well but there has been a small issue with the existing energy system that means there has been a little more fuel used than expected. With this issue, the systems have still covered 70% of the business’s energy demand over this period. The installation of the solar array has reduced the expected operating time of the diesel generator by 200 hours over this period, meaning 1000 litres of fuels have not been used, saving £500 (diesel price at £0.50 per litre).
3. Period - 1st June 2017 until 30th Setember 2017
The array has continued to work without a fault over the winter but the number of daylight hours available and a technical issue with the energy system already in place, has resulted in more fuel being used than anticipated. However, the systems have still covered 30% of the business’s energy demand over this period. The installation of the solar array has reduced the expected operating time of the diesel generator by 100 hours over this period, meaning 500 litres of fuels have not been used, saving £250 (diesel price at £0.50 per litre).
4. Period - 1st October 2017 until 31st December 2017
The array has continued to work without a fault over the spring but an issue with the existing energy system (NB/ the battery not holding charge) and the high demand of electricity for essential farming tasks, have resulted in more fuel being used than expected. With the issue, the systems have still covered over 22% of the business’s energy demand over this period. The installation of the solar array has reduced the expected operating time of the diesel generator by over 62 hours over this period, meaning 310 litres of fuels have not been used, saving £155 (diesel price at £0.50 per litre).
5. Period - 1st January 2018 until March 2018
The array has continued to work without a fault over the summer, but an issue with the existing energy system and the high demand of electricity for essential farming tasks have led to more fuel being used than expected. With the issue, the systems have covered over 22% of the business’s energy demand over this period. The installation of the solar array has reduced the expected operating time of the diesel generator, with 400 litres of fuels not being used, saving £160 (diesel price at £0.50 per litre).
6. Period – 4th April 2018 until 21st June 2018
The array has continued to work without a fault over the autumn and beginning of winter but an issue with the existing energy system with will hopefully be sorted before the spring, means there has been more fuel used than expected. With the issue, the systems have still covered over 45% of the business’s energy demand over this period. The installation of the solar array has reduced the expected operating time of the diesel generator saving 535 litres of fuels has not been used, saving £267.50 (diesel price at £0.50 per litre).
Annual Update - Saunders Island Farm
The aim of this installation is to demonstrate that a small/medium size array would be an ideal addition to a Wind Hybrid Electricity Generation system for a farm business, and give adequate electricity for most of the business and domestic tasks on site in the periods when the wind is not blowing sufficiently enough.
The 4kW solar array was commissioned on Saunders Island on the 15th August 2016 and has worked without fault for over a year to 31st December 2017 (503 days). However, there has been an issue with the existing battery bank not holding charge. With this issue, the Wind turbine and Solar array has still covered 64% of the electricity demand of the property, and the addition of the Solar Array has helped to save an estimated 960 of operational hours of the diesel generator, representing 2,880 litres of diesel which equates to a saving of £1,440 (diesel price at £0.50 per litre). When planning the installation of the 4kW array it was estimated that the array would save around £500 per year in diesel cost and have a payback of 8.5 year. The array has currently performed at 210% better than expected, mainly because the solar data available for the Falkland Islands is very conservative. If the array continues to perform as it has in the first year of generation, the payback is estimated to be 4 years.
The array has performed well but would have performed even better if the existing battery bank on site could have held a full charge, this issue will be resolved in the first quarter of 2018.
This project has demonstrated that a small to medium solar array connected to an off-grid wind hybrid system in the Falkland Islands is an ideal addition to the electricity generation system.
FIDC is committed to helping reduce the costs of running and make a business more sustainable. Our Energy Advisor is available to visit and make detailed recommendations on how this can be achieved. This case study highlights the real gains from following our guidance.